A playground for evolution
Göttingen biologists discover genome duplications in spiders and scorpions
In their attempts to understand the diversity of nature and its evolutionary mechanisms, evolutionary biologists rely on the comparative analysis of genomes. The term “genome” refers to the entirety of the genetic material that is encoded in each individual cell of an organism and contains information that dictates how species-specific morphological structures are formed. For instance, the genome of a fruit fly encodes the information for developing wings, whereas a spider’s genome contains the code for it to grow spinnerets and venom glands. Thus far, a duplication of the genome has only been determined for vertebrates. Now, for the first time, an international team of scientists collaborating with the University of Göttingen has found that the genomes of spiders and scorpions similarly underwent duplication. The results have been published in the scientific journal BMC Biology.
Indeed, humans have two copies of numerous genes, whilst fish often have as many as four copies. Evolutionary biologists assume that such genome duplications provide rich genetic material for new morphological innovations. They speak of a "playground for evolution” in this context. A team, headed by scientists from Oxford Brookes University, Baylor College of Medicine's Human Genome Sequencing Center and the University of Göttingen, sequenced the genomes of a spider and a scorpion and compared their gene content to that of other animals. "We have now finally identified an animal group in which genome duplications occurred independently from those observed in vertebrate animals,” says Prof. Alistair McGregor of the Oxford Brookes University. "For the first time, we can compare the impact of this fascinating biological phenomenon on the occurrence of innovations.”
"Using factors involved in the embryonic development of all animals studied to date, we were able to show how the duplication of the genetic material during evolution can result in new gene functions – step by step,” Dr. Nico Posnien from the University of Göttingen concludes. The team has thereby laid the foundation for future projects: "Now we can understand for instance how spiders could form fascinating structures and novel organs such as spinnerets for the production of spider silk,” says Dr. Nikola-Michael Prpic-Schäper of the University of Göttingen.
Original publication: Evelyn E. Schwager et al. The house spider genome reveals an ancient whole-genome duplication during arachnid evolution. BMC Biology. http://bmcbiol.biomedcentral.com/articles/10.1186/s12915-017-0399-x
Dr. Nico Posnien
University of Göttingen
Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology
Department of Developmental Biology – Ernst Caspari House (GZMB)
Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
Phone +49 (551) 39-20817